fix no more LegendMarkers when Series has no name

src/cuteControl.h

@@ -144,7 +144,8 @@ public:
             tooltip.replace(tooltip.find("@X"), 2, "%1");
             tooltip.replace(tooltip.find("@Y"), 2, "%2");
         }
-        emit s_plotXYSeries(s, plot, properties.onTop, properties.legend, tooltip.c_str());
+        bool legend = properties.legend & !properties.name.empty();
+        emit s_plotXYSeries(s, plot, properties.onTop, legend, tooltip.c_str());
     }
 
     void plotValues(std::vector<float>& values, int plot, const cute::PlotProperties& properties = {})
@@ -179,7 +180,8 @@ public:
         series->setName(properties.name.c_str());
         series->moveToThread(QApplication::instance()->thread());
 
-        emit s_plotBarSeries(series, plot, properties.onTop, properties.legend);
+        bool legend = properties.legend & !properties.name.empty();
+        emit s_plotBarSeries(series, plot, properties.onTop, legend);
     }
 
     void highlightValue(float value, int plot, const cute::Color& color)
@@ -221,7 +223,8 @@ public:
         s->setPen(pen);
         s->setName(properties.name.c_str());
         s->moveToThread(QApplication::instance()->thread());
-        emit s_plotXYSeries(s, plot, properties.onTop, properties.legend);
+        bool legend = properties.legend & !properties.name.empty();
+        emit s_plotXYSeries(s, plot, properties.onTop, legend);
     }
 
     void resetPlot(int plot) { emit s_resetPlot(plot); }